weaponsfandomcom-20200222-history
Heckler
The Heckler & Koch MP5 is a submachine gun which is prodcuded by Germany 1966-present. It is usually used by Special Forces units such as the SAS (British Special Air Services). Design The primary version of the MP5 submachine gun family is the MP5A2, which is a selective-fire roller-delayed blowback operated weapon. The bolt mechanism consists of a bolt head and bolt carrier. After firing, the rollers integrated into the bolt head are cammed inward against the inclined planes of the barrel extension and locking piece by rearward pressure on the bolt head. As the rollers are forced inward they displace the locking piece and propel the bolt carrier to the rear. The bolt carrier's rearward velocity is four times that of the bolt head since the bolt remains locked for a short period of time after the initial recoil impulse. After the bolt carrier has traveled rearward 4 mm, the rollers on the bolt head (which has moved only 1 mm) are compressed in, unlocking the bolt, opening the breech, and the two parts continue their backward movement together. Since the 9x19mm Parabellum cartridge is relatively “weak”, the bolt does not have an anti-bounce device, but instead the bolt carrier contains tungsten granules that prevent the bolt from bouncing back after impacting the barrel extension. The weapon has a fluted chamber that enhances extraction by bleeding gas backwards to loosen the spent cartridge from the chamber walls (the bolt is opened under relatively high barrel pressure). A spring extractor is installed inside the bolt mechanism, while the lever-type ejector is located inside the trigger housing (activated by the movement of the recoiling bolt). The MP5 has a hammer firing mechanism. The trigger mechanism is placed inside an interchangeable trigger housing (with an integrated pistol grip) and equipped with a 3-position fire selector that is also the manual safety toggle (selector lever in the “E” Einzelfeuer position – single fire mode, “F” Feuerstoß – continuous fire, “S”, Sicher – safe – the trigger is disabled). The weapon initially used double-column straight box magazines, but since 1977 arched, steel magazines are used with a 15-round capacity (weighing 0.12 kg) or a 30-round capacity (0.17 kg empty). The MP5 is equipped with mechanical iron sights (closed type) with an adjustable rotary drum. The rear sight, adjustable for windage and elevation, has four apertures used for firing at: 25, 50, 75 and 100 m. The receiver housing has notches that permit the attachment of a standard HK adapter (also used with the G3, HK33 and G3SG/1) that can be used to mount daytime optical sights (telescopic 4x24), night sights or a halogen illuminator. It can also be used with reflex sights and laser pointers. The rifled barrel has 6 right-hand grooves at a 250 mm (1:9.8 in) twist rate and three lugs at the muzzle that are used to work with certain muzzle devices made by HK, including: a slotted flash hider, blank-firing adaptor, a base for launching rifle grenades and a cup-type attachment used to launch tear gas grenades. The MP5A2 has a fixed stock (made of a synthetic polymer), whereas the compact MP5A3 has a retractable metal stock. Included with the MP5A2 and MP5A3 are: sling, cleaning kit, quick-loading device and a clamp which holds two magazines. As an option, tritium-illuminated sights are also available (used for firing in low-level lighting conditions) as well as sound suppressors from several aftermarket manufacturers. In the early 1970s HK introduced a conversion kit for the MP5 that enables it to use sporting ammunition (.22 LR). This unit consists of a barrel insert, a bolt group and two 20-round magazines. This modification reduces the cyclic rate to 650 rounds/min. The MP5A2 and MP5A3 submachine guns are also available with optional 4-position trigger units; such-equipped weapons are known as the MP5A4 and MP5A5 (respectively). The trigger groups are marked with bullet pictograms rather than numbers and are fully ambidextrous (a selector lever on each side of the housing). The additional, fourth setting of the fire selector enables a three-shot burst firing mode. HK also offers dedicated training variants of these weapons, designated MP5A4PT and MP5A5PT, modified to fire the 9x19mm PT training cartridge that uses a bullet made of plastic. To help identify these weapons blue dots were placed on their cocking handles. Thanks to the modular design of the MP5, particularly the trigger groups, a large number of configurations are available to meet the user’s individual requirements. Currently offered are the following trigger groups: three-position selector/safety (settings: safe, semiautomatic and a 2 or 3-round burst; selector lever is ambidextrous and its settings are marked with symbols); four-position fire safety selector (settings: weapon safe, single fire, 2-round burst, full auto; ambidextrous selector; selector settings marked with pictograms); two-position fire control group (positions: “S” – weapon safe, “E” – single fire only; selector lever located on the left side of the trigger housing) and a three-position fire selector/safety group - the so called “Navy” trigger (settings: weapon safe, semi-automatic, fully automatic fire; ambidextrous selector lever/safety; selector settings marked with bullet symbols). A variant with the last trigger group designated the MP5N (N – Navy) is used by the US Navy's special operations units. Additionally this weapon is fitted with a tritium-illuminated front sight post and a threaded barrel for use with a sound suppressor made by KAC (when suppressed subsonic ammunition is used). The two-position trigger unit is used in the single-fire HK94 carbine that was produced specifically for the civilian market with a 420 mm barrel. In 1974 HK initiated design work on a sound-suppressed variant of the MP5, designated the MP5SD (SD – Schalldämpfer), which features a silenced barrel and a lightweight bolt. The barrel has 30 2.5 mm ports just forward of the chamber through which escaping gases are diverted to the surrounding tubular casing that is screwed on to threading on the barrel’s external surface prior to the ported segment. The suppressor itself is divided into two stages: the initial (surrounding the barrel) and final decompression stage (the remaining length of the suppressor tube). The muzzle portion of the suppressor (final decompression stage) contains a stamped metal helix separator with several compartments, which increase the gas volume and decrease its temperature. As a result of reducing the barrel’s length and bleeding exhaust gases through ports in the barrel the bullet’s muzzle velocity was dropped to a subsonic level while maintaining the weapon’s automation and reliability. The MP5SD is produced exclusively by HK in six versions: the MP5SD1 and MP5SD4 (both lacking a stock, replaced with a receiver endplate cover), MP5SD2 and MP5SD5 (both featuring a fixed stock) and the MP5SD3 and MP5SD6 (with collapsible metal stocks). The MP5SD1, MP5SD2 and MP5SD3 use a standard trigger group (from the MP5A2 and MP5A3), while the MP5SD4, MP5SD5 and MP5SD6 – a trigger group with a mechanically limited burst mode (from the MP5A4 and MP5A5). In 1976 a shortened version of the MP5A2 was introduced, the MP5K (K – Kurz), designed with clandestine operations and special services in mind primarily for close quarters battle. This SMG does not have a shoulder stock (the receiver end was covered with a flat cover), and the bolt and receiver were shortened at the rear. The resultant lighter bolt led to a higher rate of fire than the standard MP5. The barrel, cocking handle and its cover were shortened and a vertical foregrip was used to replace the standard handguard. The barrel ends at the base of the foresight, which prevents the use of any sort of muzzle device. MP5K submachine guns are produced (by HK and under license in Iran and Turkey) in four different versions: the MP5K, MP5KA4, MP5KA1, MP5KA5, where the first two variants have adjustable, open-type iron sights (with a notched rotary drum), and the two remaining variants - fixed open sights, however the front sight post was changed and a notch was cut into the receiver top cover. The MP5K retained the capability to use optical sights through the use of an adapter. Category:Post WWII Submachine guns